In Greek mythology, Pandora’s original container was usually called a jar. The Greek word used in ancient sources is pithos, a large storage jar commonly used for grain, oil, or wine.
The familiar phrase “Pandora’s box” developed later through translation history. The sixteenth-century humanist Erasmus translated the Greek vessel into Latin as pyxis, meaning a box or small container. That choice helped establish the wording now common in English and many other languages.
Hesiod’s Works and Days describes Pandora opening the vessel and releasing troubles into the world. The story is therefore not originally about a hinged wooden box. Modern illustrations often show a decorated box because that image matches the later phrase. The jar’s storage function also fits the myth’s imagery: it held something concealed and potentially dangerous until it was opened.